The present invention relates generally to the field of stencils for use in the construction industry. In particular, the present invention relates to a template for laying out multiple entry holes for passage of conduit into an electrical panelboard.
In the construction industry, electrical wires are often run through piping to safely deliver power to and from a panelboard and then onto different areas of a building. This piping, referred to as “conduit” in the trade, is typically constructed from metal or plastic and comes in a variety of sizes standard to the electrical industry. The size of conduit used to run a particular electrical line depends both upon the length of the run as well as the particular power application.
Running conduit from a panelboard to distant areas of a building frequently requires an electrician to make numerous entry holes for passage of conduit both into and out of an electrical panelboard, as well as potentially through walls and ceilings. Often times multiple rows of columns of conduit must be installed, such as when wiring a panelboard. The configuration of the conduit is often maintained until the conduit branch off to reach different areas of a building. As such, an electrician may be required to make the same hole-cut pattern on, for example, the top surface of a panelboard and a ceiling suspended above.
Under the traditional method for laying out the positions of conduit entry holes on the top of a panelboard housing, an electrician uses a ruler or tape measure to measure the location of each particular entry hole. In doing so, the electrician must take into account the spacing of each conduit from a wall surface on which panelboard is located to allow for the thickness of the strut used to secure the conduit to the wall surface. In addition, the electrician must account for the spacing between each conduit, which typically conforms to industry standards such as those proscribed by the National Electrical Contractors Association (NECA).
The traditional method for laying out entry holes on a panelboard has several drawbacks. When multiple rows and/or columns of conduit are to be installed the task of marking the locations of the conduit entry holes can become a time consuming and tedious task. Although the electrician may need to replicate the same pattern of entry holes in multiple surfaces, each hole in each installation must be individually measured. In addition, under the traditional method, errors in measuring often occur, resulting in wasted labor and materials.
Measuring aids for speeding up the measurement process are known. U.S. Pat. No. 5,577,328 discloses a stencil with pre-measured markings to aid in the measuring process. The stencil is capable of measuring a variety of conduit entry hole sizes. However, an electrician using the stencil can lay out only one entry hole at a time, and must reposition the stencil before measuring an adjacent entry hole. In addition, the stencil does not account for the thickness of strut used to secure the conduit to a wall surface. Thus, the measuring process still requires a multitude of measurements and an opportunity for error exists when repositioning the template for each individual entry hole.
U.S. Pat. No. 4,584,780 also discloses a template for laying out conduit entry holes on an electrical panelboard. The template, however, must also be repositioned to measure each entry hole and does not account for the thickness of strut used to attach the conduit to a wall surface.
Given the limitations of the prior art, a more systematic measuring template and measuring method is needed to speed the accuracy and timing of conduit installations, especially for multiple-conduit installations.